Update for 1.73 Beta 1.

Fix issue MR-592 - Unable to run VBS script as an external tool

Fix issue MR-596 - Incorrect escaping of quotation marks in external tool arguments

Update CHANGELOG.TXT for 1.71 RC3.

Update CHANGELOG.TXT for 1.71 RC3.

Update CHANGELOG.TXT for 1.71 RC2.

Update CHANGELOG.TXT for 1.71 Beta 5.

Update CHANGELOG.TXT for release of 1.71 Beta 4.

Fix PuTTY saved sessions with spaces or special characters not being …

…listed.

Update CHANGELOG.TXT for release of 1.71 Beta 2.

Prepare CHANGELOG.TXT for release of 1.70 RC3.