Improve sending web link with Bluetooth

When sending web link from Google maps app, link cannot be used by
receiver as maps app will send extra text in addition to web link.

Improve the creation of html so that only the web link is
interpreted as a link.

Code is partly copied from MessageView class in the email app.

Change-Id: Idb093cc3d5af5fa6b85649d194fa6dc0c6fdfd1e
Use round() instead of ceil() in calculation of a2dp vol slider position

The avrcp MESSAGE_VOLUME_CHANGED requests volumes in the range 0-127. In
convertToAudioStreamVolume() this value is scaled to a (typically much
smaller, e.g. 0-15) integer value representing the volume slider step to
be presented in the UI. Depending on the resolution in the volume
requests from the a2dp device and the resolution of the UI volume
slider, some of the requested volumes might be mapped onto the same
UI slider positions. If ceil() is exchanged for round() in
convertToAudioStreamVolume() the problem with double mapped volumes
vanishes in most realistic cases.

Change-Id: I89d9ac4b8c330fd4fd2a02984bd628961f2cb035
HFP: Fix missing OK for AT+CLCC in virtual call

When AT+CLCC is received from HF while we're in virtual call mode there
is only non-zero index call sent without final zero index call. This
makes AT command response incomplete since no OK is sent.

From HFP specification, section 4.31.1:
"The AG shall always send OK response to HF."

Change-Id: I2d759bd3d65f2adb9a364d40ffe23d6197c6375b