Miscellaneous text fixes for core apps

apps/files_encryption/appinfo/info.xml

@@ -2,7 +2,7 @@
 <info>
 	<id>files_encryption</id>
 	<name>Encryption</name>
-	<description>The ownCloud files encryption system provides server side-encryption. After the app was enabled you need to re-login to initialize your encryption keys. Please note that server side encryption requires that the ownCloud server admin can be trusted. The main purpose of this app is the encryption of files that are stored on externally mounted storages.</description>
+	<description>The ownCloud files encryption system provides server side-encryption. After the app is enabled you need to re-login to initialize your encryption keys. Please note that server side encryption requires that the ownCloud server admin can be trusted. The main purpose of this app is the encryption of files that are stored on externally mounted storages.</description>
 	<licence>AGPL</licence>
 	<author>Sam Tuke, Bjoern Schiessle, Florin Peter</author>
 	<require>4</require>

apps/files_versions/appinfo/info.xml

@@ -9,7 +9,7 @@
 	<description>
 	ownCloud supports simple version control for files.	The versioning app
 	expires old versions automatically to make sure that
-	the user doesn't run out of space. Following pattern is used to delete
+	the user doesn't run out of space. The following pattern is used to delete
 	old versions:
 	For the first 10 seconds ownCloud keeps one version every 2 seconds;
 	For the first hour ownCloud keeps one version every minute;

apps/user_ldap/appinfo/info.xml

@@ -2,8 +2,8 @@
 <info>
 	<id>user_ldap</id>
 	<name>LDAP user and group backend</name>
-	<description>Authenticate users and groups by LDAP respectively Active
+	<description>Authenticate users and groups through LDAP, such as OpenLDAP
-		Directory.
+	    or Active Directory.
 
 		This app is not compatible with the WebDAV user backend.
 	</description>

apps/user_webdavauth/appinfo/info.xml

@@ -4,7 +4,7 @@
 	<name>WebDAV user backend</name>
 	<description>Authenticate users by a WebDAV call. You can use any WebDAV server, ownCloud server or other webserver to authenticate. It should return http 200 for right credentials and http 401 for wrong ones.
 
-	This app is not compatible to the LDAP user and group backend.</description>
+	This app is not compatible with the LDAP user and group backend.</description>
 	<licence>AGPL</licence>
 	<author>Frank Karlitschek</author>
 	<require>4.93</require>