Advise Project Manager for a small studio

Good evening everyone . I appeal for advice to a large audience of Habrahabr for advice. There is a small team of web developers, or you can put it that way web studio. With the increase in orders they began to face the compilation of TODO for each day and the distribution of tasks for each taken member of the studio, but they came to the conclusion that there is no necessary means for settling these tasks. Therefore, the question arose in finding a Project Manager in which it will be possible to conduct all projects. I want him to have many necessary criteria, such as:

Employee management
Project management
Customer Management *
Keep track of the time spent on a certain part of the project, the entire project and other statistics
A bugtracker is required in which bugs from clients will be accepted and further investigation of the bug will be conducted.

We rummaged through several similar things, for example: TrackStudio, Trac, SugarCRM, now we are dealing with the latter, but they are too bloated and in some way are not suitable for us.
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If someone faced with a detailed problem, tell me what you can choose for us for convenient collaboration and management. Express what tools you use to solve such problems.

PS We work in Linux , so Windows solutions will not help us.